Drug-related problems continue to be a major source of concern in the United States. Specifically, cigarette smoking, alcohol, and other drug use are associated with a wide variety of illnesses, deaths and other negative consequences. Substance abuse has huge costs for society. Adolescence is the critical period to intervene to prevent drug abuse before it begins or escalates. As ethnic minority groups have become the target of cigarette and alcohol advertising recently, inner-city youth are at greater risk of initiating drug use and deserve further attention. Before effective programs can be implemented with multi-ethnic urban youth, research elucidating the etiology of drug use among these predominantly minority adolescents is necessary. This application proposes secondary data analysis to examine predictors of poly-drug use (cigarette smoking, alcohol use, and marijuana use) for multi-ethnic, inner-city youth; make ethnic comparisons for poly-drug use among four ethnic groups (Asians, Blacks, Hispanics, and Whites); and investigate the role of linguistic accumulturation in poly-drug use among Hispanic adolescents. This study would capitalize on data already collected as part of a large-scale prevention trial that was funded by NCI to assess the efficacy of a cognitive-behavioral skills training program on smoking. The proposed study will examine untreated control subjects only from a longitudinal cohort during the middle school/junior high school period. The panel design will focus on three assessments: (1) the baseline measurement, (2) the one-year follow-up, and (3) the two-year follow-up. Self-reported measures assessed a wide range of constructs expected to relate to adolescent drug use: social influences for drug use (such as friends' use and normative beliefs about drug use), social skills efficacy, assertiveness, decision-making, self-efficacy, self-esteem, risk-taking, and psychological distress. This research is significant because it will increase our understanding of the etiology of drug use in understudied ethnic minority groups residing in inner-city regions. Both cross-sectional and longitudinal analyses of adolescent drug use among inner-city adolescents will be conducted. Findings from this research will provide information relevant to development of more effective drug abuse prevention approaches for multi-ethnic, inner-city populations.